Exception Hierarchy [WAS: Re: Top 5]

[Sean Kelly]

Bruno Medeiros wrote:
> 
> I agree there should be a distinction between recoverable exceptions 
> (normal exceptions) and nonrecoverable exceptions (contract failures?). 
> I agree that "Exception" should be the name for normal exceptions. The 
> others could be named "Error" or "Failure".
> If we want the ability to catch these two separately, I don't see any 
> other way other than having a third, top-level class, ie, a "Throwable", 
> from which Exception and Error/Failure derive from.

This is exactly the design that was decided upon.

> But while one will certainly want to catch Exception's without catching 
> Error's, I'm not 100% sure it would be useful to be able to easily catch 
> an Error but not an Exception. Does anyone know of such a case?

Possibly for reporting purposes--catch an Error to test if a critical 
error occurred, then re-throw.  But I've never had a need for this 
myself.  One could argue, then, that these should all simply derive from 
Throwable, but I think the logical grouping is useful for classification 
purposes if nothing else.


Sean